With the increased use of underground utilities, there is a need to locate and verify the placement of buried utilities before installation of additional underground utilities or before other excavation or digging work is performed. Reduction systems are among the prior art systems that are used for removing soil to expose underground utilities such as electrical and cable services, water and sewage services, etc. A prior art vacuum operated earth reduction system typically comprises a mobile chassis, a central collection tank under vacuum mounted to the chassis, a water pump mounted to the chassis, a vacuum pump connected to the collection tank, at least one backfill reservoir for carrying backfill mounted on the chassis, and a water reservoir tank. The water reservoir tank contains clean water.
The water reservoir tank for the clean water has a hole or an opening with a screw cap with a threaded connection at the top of the tank. A user climbs a ladder to the top of the tank and unscrews the cap. If there is no pipe connection for the hose/water source (described below), the user holds the hose end above the tank opening and allows the water to flow into the tank while holding the hose. The user does not, however, attach the hose end into the tank opening. Instead, there is a gap between the end of the hose and the tank opening. The other end of the hose is connected to a clean water source such as a spigot or a fire hydrant.
The gap accommodates government regulations that require that a water source connected to a public water system not be connected in a pressure-sealed manner directly to the tank because of the risk that back pressure could allow a path for contents of the tank to flow back into the public system. If the water source is so connected to a closed volume, there is an increased possibility of high pressure in the enclosed volume, causing reverse flow back into a public water line and resulting in possible contamination to the public water supply, for example. Thus, where the hose is connected at the back end directly to the municipal water source, which provides pressure to the hose and at the nozzle at the hose's forward end, the hose is not attached at a sealed connection to the closed tank.
It is also known to provide a pipe at the side of the tank that extends from a position near the lower part of the tank/chassis, accessible to a user standing at ground level, up to the top of the tank. A hose extending from a municipal water source is attached in a sealed manner to this lower end of the pipe. The pipe then extends up the tank's side to the top of the tank and ends at a point offset from the capped hole in the top of the tank, leaving a gap between the end of the pipe and the cap. The gap allows the user, having climbed to the top of the tank via a ladder, to access and remove the cap and allows for a gap during water flow to prevent back pressure. The gap, however, can allow contaminants to enter the tank through the open gap when the tank is being filled. Further, while the pipe relieves the user of the need to haul the hose up to the tope of the tank, the user must nonetheless climb the tank to remove the cap. Generally, the hole/cap are disposed at the top in these systems because the water tank is not pressurized and water fills in the tank by downward flow.
Thus, there is a need for a device for filling a water reservoir tank in an earth reduction system that overcomes these known disadvantages and that does not require an individual to climb to the top of the tank every time the tank needs to be filled and, in certain embodiments, inhibits the escape of water from inside the tank and the entrance of contaminants into the tank.